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Find slope :
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When the slope is 0, the graph is a horizontal line.
Equation of the graph is y = -4
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Answer: y = -4------------------------------------------------------
If you look at the points, you can find out
Proof method:
1. Calculate the length of each side, DE,DF,EF
2. Compare the length of them, if any pair of them is equal, then it's isosceles.
Answer:
x<11
Step-by-step explanation:
x+10<21
-10 -10
x<11